geometry vocab Flashcards
location with no size or shape
point
made up of points with no thickness or width
line
a measurable part of a line consisting of two endpoints
line segment
a line that extends indefinitely in one direction
ray
a flat surface made up of points and extends indefinitely in all directions
plane
points that lie on the same line
collinear
points that lie on the same plane
coplanar
segments that have the same length
congruent segments
if a, b, and c are collinear points and b is between a and c, then line ab + line bc=ac
segment addition postulate
the formula used to find the midpoint between 2 endpoints
midpoint formula
the formula used to find the distance between 2 points of a coordinate plane
distance formula
a segment, line, or plane that intersects a segment at its midpoint
segment bisector
two lines that intersect at a 90 degree angle
perpendicular
A line segment or ray perpendicular to a segment at its midpoint
Perpendicular bisector
two lines that never intersect
Parallel lines
The intersection of two rays at an endpoint
Angle
The common endpoint of an angle, where the sides intersect
Vertex
an angle with a degree measure of 90°
Right angle
an angle with a degree measure of less than 90°
acute angle
An angle with a degree measure of greater than 90°
Obtuse angle
An angle with a degree measure greater than 90°
Obtuse angle
an angle with a degree measure of 180 degrees
Straight angle
two angles that have the same measure
Congruent angles
two angles that share a common side in vertex
Adjacent angles
if ABD and DBC are adjacent then ABD plus DBC equals ABC
Angle addition, postulate
A line or ray that divides an angle into two equal parts
Angle bisector
two angles directly across from each other on intersecting lines, always congruent
Vertical angles
Two angles with measures that sum to 90° they do not have to be adjacent
Complementary angles
two angles with measures that sum to 180° they do not have to be adjacent
Supplementary angles
Adjacent angles that are supplementary. Combined, they form a straight line.
linear pair
